Golf is governed by The Rules of Golf as approved by the United States Golf Association and the Royal and Ancient Golf Club of St. Andrews, Scotland, referred to herein as the USGA Rules. The most current rules are available from www.USGA.org. A typical game of golf is played on a course having 18 holes and a golfer may carry up to 14 clubs with him during play. An average golfer uses over 80 strokes to complete the game, and typically half of those stokes are putts. Therefore, the putter is by far the most important of the regulation 14 golf clubs in a golfer's bag, and improved putting will improve a player's score more than improvement in any other stroke.
Consequently, thousands of devices and methods have been devised to help a golfer improve his putting, ranging from the practical to the absurd. Most of these devices do not conform to the design of clubs specified by the USGA Rules, however, and therefore are used during practice only. The golfer must switch putters to play a round of golf, thus changing the primary tool with which he perfected his stroke. As a result, the putt stokes during play are seldom as good as during practice. It would be advantageous, then, to provide a dual-purpose putter that conforms to the Rules of Golf so that the golfer can use the same putter in practice as in play.
Under the USGA Rules, the putter shall have a shaft and a head, fixed to form one unit. When the golf club is in its normal position to address the ball, the shaft shall be aligned so that the projection of the straight part of the shaft onto the vertical plane through the toe and heel shall diverge from the vertical by at least 10 degrees. Further, the projection of the straight part of the shaft onto the vertical plane along the intended line of play shall not diverge from the vertical by more than 20 degrees. The USGA Rules further require that the clubhead meet specific criteria. For example, the distance from the heel to the toe of a putter shall be greater than the distance from the play face to the back. These rules limit the orientation of the shaft to the clubhead, and therefore the balance of the putter, a major factor in aligning the ball and in putting consistently.
The penalty for playing a game of golf with a putter that does not conform to the USGA Rules is disqualification from the game. However, with the many rules pertaining to the design of putters, it is difficult to design a club that provides quality training features for practicing and yet can be used for play. It is desirable to provide a single putter that can be converted from a practice putter to a play putter that conforms to USGA Rules.
Therefore, it is an object of this invention to provide a putter that enables the golfer to determine which strokes are the best during practice so that he may practice those strokes repeatedly and learn to stroke the ball consistently in play. It is another object of this invention to provide a single putter that can be used for both practice and play. It is another object to provide a single putter that can be converted from a practice putter to a play putter that conforms to the USGA Rules. It is an object of this invention to provide a putter in which the shaft always diverges at least 10 degrees from the sole of the clubhead, regardless which orientation the golfer holds the putter when addressing the ball.